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I I Grachev

Publications and source records attributed to I I Grachev.

At least 19 recordsLinked to original sources
PubMed1983

[Morphological studies of the neurons of the area of the hypothalamic supraoptic nucleus in rats in diffusion chambers].

A method of diffusion chambers was used for hypothalamic tissue culturing. Chambers containing fragments from the supraoptic nucleus region of young rats-donors were implanted to rats-recipients. The processes of cell differentiation and interneuron interactions were studied by light and scanning electron microscopy. Morphological peculiarities of the main neuron types of the culture investigated suggest that the large differentiated multi- and bipolar neurons are the neurosecretory cells of the supraoptic nucleus. In the culture investigated small multipolar neurons of this nucleus and perinuclear areas were also present. The results give the possibility to consider the method of diffusion chambers as a promising one for the investigation of neurosecretory hypothalamic regions.

Animals↗
PubMed1981

[Effect of central administration of leu-enkephalin on neurosecretory cells of the paraventricular nucleus of the hypothalamus and enterochromaffin cells of the stomach].

Administration of enkephalin into the 3rd ventricle enhanced the excitability of the paraventricular nucleus neurosecretory cells, the excitability reaching its maximum within 10 min. By the 15th min after the enkephalin administration the number of the enterochromaffin cells increases suggesting the inhibition of the secretory granules contents release into the blood. Within next 15 min the excitability of the hypothalamic neurosecretory neurons returns to its normal level. A simultaneous sharp decrease of the enterochromaffin cells occurs suggesting an endogenous activation of the secretory granules contents release.

Animals↗
PubMed1979

[Morphofunctional interrelationships between the hippocampus and hypothalamus in rats].

Evoked reactions of the hypothalamic arcuate and medial preoptic nuclei neurons were recorded when the hippocampus was stimulated by single stimuli in anaesthetized rats. In the arcuate nucleus phasic responses and primary inhibition were found to be dominant and in the medial preoptic nucleus--both phasic and nonspecifical responses. After injection of the horseradish peroxidase into the stimulated hippocampal region stained cells were found in the nuclei of the mammillary complex, mediobasal hypothalamus and in the medial preoptic nucleus. Groups of stained neurons were observed in the periphery of ventro- and dorsomedial, lateral and mammillary nuclei of the hypothalamus. In all the studied structures, except the medial mammillary nucleus, reticular-like cells were found alongside with spindle-like and triangle neurons. The data obtained are discussed in connection with the problem of hypothalamo-hippocampal interaction.

Animals↗
PubMed1979

[Responses of individual receptor units of rat mammary gland parenchyma to tactile stimulation].

Two types of slowly adapting mechanosensitive units were revealed in the parenchyma of the rat mammary gland (SAI and SAII). At constant mechanical displacement of the parenchyma surface SAI exhibited irregular and SAII--regular firing. The diameter of the receptive fields of the SAI and SAII was 1.0--1.5 mm with the central point of this area being the most sensitive. Trapezoidal stimuli elicited both dynamic and static responses proportional to the velocity of the movement and its displacement amplitude; the threshold of the SAI and SAII increased as stimuli of increasing velocity were used.

Action Potentials↗
PubMed1979

[Effect of inhibitors of the active transport of ions on the spontaneous and evoked electrical activity of parenchymal mammary gland receptors].

In the potassium-free saline spontaneous activity of the mammary gland parenchyma receptor increased within first 30--40 min., then decreased and, finally, ceased. Sensitivity of the receptor to the mechanical stimuli decreased gradually. After washing in normal saline the evoked and spontaneous activities recovered. Ouabain (5 . 10(-5)--10(-4) g/ml) exerted an effect similar to that of the potassium--free solution except that the impulse activity could not be restored by the washing in physiological saline.

Action Potentials↗
PubMed1978

[Effect of isadrine and propranolol on the membrane potential of mammary secretory cells].

1.10(-7)--1.10(-5) g/ml of isadrine induced a 2-phase hyperpolarization changes of MP of the secretory cell. Propranolol (1.10(-6) g/ml) decreased the amplitude of hyperpolarization response of the MP to oxytocin by 36%; 1.10(-9)--1.10(-8) g/ml of isadrine induced a 42% and 53% decrease respectively, and 1.10(-7)--1.10(-5) g/ml blocked the response of secretory cells to oxytocin. The data obtained suggest that catecholamines can effect the MP by means of interaction with beta-adrenoreceptors of mammary secretory cells.

Animals↗
PubMed1978

[Distribution of oxygen tension in breast tissues].

Using a mathematical model which describes the O2, transport in the alveolar cell of the mammary gland, the distribution of pO2 levels during two stages of the secretory cycle, was calculated. At the initial stage, the typical feature of which is the increased blood flow and O2 consumption, pO2 in the secretory tissue varied from 3 to 30 torr (average 9.9 torr). At the later stage of the secretory cycle characterized by the decreased blood flow and O2 consumption, pO2 levels in the secretory tissue were within the limits of 40--60 torr (average 48.9 torr). The increase of blood flow usually observed at the initial stage of the secretory cycle seems to supply tissues with the necessary amount of O2 even if the capillarization of the alveoli is minimal.

Animals↗
PubMed1978

[Dynamics of blood circulation and oxygen consumption in mammary glands].

In lactating albino mice, the blood flow rate and oxygen consumption in mammary tissues varied with a period of 45--50 min. The maximal values were reached at the initial stage of the secretory cycle: oxygen consumption 9.7 +/- 2.5 ml O2/100 g.min, and blood flow 94.3 +/- 21.2 ml/100 g.min. The minimal values of oxygen consumption and blood flow ere recorded on the 30--35th min of the secretory cycle and were 1.2 +/- 0.4 ml O2/100 g.min and 16.2 +/- 5.3 ml/100 g.min, respectively. Oxygen consumption by the secretory cells at the beginning of the secretory cycle averaged 19.3 +/- 5.2 ml 92/100 g.min, and within 30--35 min--3.3 +/- 1.1 ml O2/100 g.min. The linear relations between the intensity of blood flow and oxygen consumption in the mammary gland were revealed.

Animals↗
PubMed1978

[Change in the shape and volume of the secretory cells of the mammae in the course of the secretory cycle].

Changes occurring in the acini due to oxytocin were studied using the vital photometry and the morphometric analysis of materials obtained by biopsy. At the initial stages of the functional activation, the secretory cells become cylindric, their volumes simultaneously increasing. A study of intercellular interrelations using the atropine blockade of cholinoreceptors, revealed the lack of activation of the secretory cycle which suggests the functional dissociation of contractile and secretory functions of the cell alveolar complex.

Animals↗
PubMed1978

[Localization of cholinesterases in structures of the alveolar portion of the mammary gland].

Cholinesterase (ChE) localization in the alveolar compartment of the mammary gland has been studied by light microscopy and ultrahistochemical methods. The product of reaction to ChE is associated with micropinocytotic vesicles of the capillar endothelium and myoepithelial cells, separate nerve terminals in interalveolar connective tissue and perivascular nerve terminals. In secretory cells, the ChE activity is revealed in the sites of fat droplet and on the membranes of endoplasmatic reticulum.

Animals↗